Does excessive low-voltage power supply output ripple on the BMS control board reduce the immunity of digital circuits?

Yes, excessive low-voltage power supply output ripple can significantly reduce the immunity of digital circuits. Power supply ripple is essentially AC noise superimposed on a DC voltage. Excessive ripple reduces the noise margin of digital ICs, making them more susceptible to logic errors when subjected to external interference. Simultaneously, ripple can couple to other circuits through the power network. The solution is to optimize the filtering and regulation design of the low-voltage power supply. Use LC or π-type filters at the power module output, such as using ferrite beads in series combined with multiple capacitors in parallel. Ensure a stable feedback loop by selecting low-noise LDOs or switching regulators. Place high-quality decoupling capacitors near the power pins of critical digital ICs to provide a clean local power supply.